What are ranchers called that fatten young cattle?

Ranchers who fatten young cattle are typically called feedlot operators or cattle feeders.

Here's why:

* Feedlot: This term specifically refers to a large, confined area where cattle are intensively fed to rapidly gain weight before slaughter.

* Cattle feeder: This term emphasizes the role of the rancher, which is to feed and care for the cattle in the feedlot.

While "rancher" can be a general term, it doesn't always specify their specific activity. Using "feedlot operator" or "cattle feeder" is more precise and accurate when describing someone who specializes in fattening young cattle.